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I'm Stephen Koo, a Senior Software Engineer based in New York, NY, working on scalable web apps and AI-powered interfaces used by millions. I love building real-time experiences and elegant frontend architectures that ship fast and scale smoothly. I specialize in modern frontend ecosystems using React, Next.js, and Angular for real-time AI experiences, designing interactive AI assistants, streaming UIs, and full-stack platforms that integrate large language models with cloud services.…I'm Stephen Koo, a Senior Software Engineer based in New York, NY, working on scalable web apps and AI-powered interfaces used by millions. I love building real-time experiences and elegant frontend architectures that ship fast and scale smoothly. I specialize in modern frontend ecosystems using React, Next.js, and Angular for real-time AI experiences, designing interactive AI assistants, streaming UIs, and full-stack platforms that integrate large language models with cloud services.

Stephen Koo

Full Stack Developer, Front-End Developer, Back-End Developer, +2

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I'm Stephen Koo, a Senior Software Engineer based in New York, NY, working on scalable web apps and AI-powered interfaces used by millions. I love building real-time experiences and elegant frontend architectures that ship fast and scale smoothly. I specialize in modern frontend ecosystems using React, Next.js, and Angular for real-time AI experiences, designing interactive AI assistants, streaming UIs, and full-stack platforms that integrate large language models with cloud services.…I'm Stephen Koo, a Senior Software Engineer based in New York, NY, working on scalable web apps and AI-powered interfaces used by millions. I love building real-time experiences and elegant frontend architectures that ship fast and scale smoothly. I specialize in modern frontend ecosystems using React, Next.js, and Angular for real-time AI experiences, designing interactive AI assistants, streaming UIs, and full-stack platforms that integrate large language models with cloud services.

Available to hire

I’m Stephen Koo, a Senior Software Engineer based in New York, NY, working on scalable web apps and AI-powered interfaces used by millions. I love building real-time experiences and elegant frontend architectures that ship fast and scale smoothly.

I specialize in modern frontend ecosystems using React, Next.js, and Angular for real-time AI experiences, designing interactive AI assistants, streaming UIs, and full-stack platforms that integrate large language models with cloud services.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Language

English

Fluent

Work Experience

Senior Software Engineer at Google

October 1, 2017 - Present

Built Workspace AI Assistant panel using React.js, Next.js, and TypeScript, enabling contextual AI assistance directly in Gmail and Google Chat used by millions. Designed and implemented real-time suggestion rendering powering Smart Compose and AI-generated suggestions, supporting streaming responses and low-latency interactions. Developed an internal AI platform control plane UI for ML teams to configure models, run A/B tests, and monitor real-time performance metrics. Implemented SSR and streaming UI architecture in Next.js to support responsive AI interactions and reduce perceived latency. Built a Node.js API gateway aggregating data from Gmail, Drive, and Calendar to construct contextual prompts for AI-powered experiences. Collaborated with ML engineers to integrate Vertex AI and Gemini models into Gmail features including AI-assisted drafting, tone rewriting, and conversation summarization. Implemented RAG pipelines using semantic embeddings and internal vector search to improve c